Organ system for automatically producing runs of various character

ABSTRACT

An electronic organ system which automatically plays an arpeggio, a glissando, or a whole tone scale of notes when a supplementary miniature keyboard is stroked. The miniature keyboard is under the control of the lower keyboard, (the control keys) such that holding control keys determines which miniature keys are live (will play). If no control keys are held, all miniature keys are live. If control keys in one whole tone scale only are held, all miniature keys in the same whole tone scale are live. Others are dead. If control keys in both whole tone scales are held, only the same keys and those in octave relation thereto in the miniature keyboard are live.

United States Patent [1 1 Petrie [451 Dec. 18, 1973 ORGAN SYSTEM FOR AUTOMATICALLY PRODUCING RUNS OF VARIOUS CHARACTER [75] Inventor: Adelore F. Petrie, Arlington [21] Appl. No.: 324,238

[52] U.S. Cl 84/l.l7, 84/1.24, 84/DIG. 22

[51] Int. Cl. GlOh 1/00 [58] Field Search 84/l.0l, 1.17, 1.24,

84/DlG. 22, DIG. 25

3,432,607 3/1969 Bergman 84/l.17 3,617,602 11/1971 Kniepkamp 84/l.17 3,651,729 3/1972 Adachi 84/1.17

Primary Examiner-Richard B. Wilkinson Assistant Examiner-Stanley J. Witkowski Attorney-Gradolph & Rogers [5 7] ABSTRACT An electronic organ system which automatically plays an arpeggio, a glissando, or a whole tone scale of notes when a supplementary miniature keyboard is stroked. The miniature keyboard is under the control of the lower keyboard, (the control keys) such that holding control keys determines which miniature keys are live (will play). If no control keys are held, all miniature keys are live. 11' control keys in one whole [56] References Cited tone scale only are held, all miniature keys in the same U TED S ATE PATENTS whole tone scale are live. Others are dead. 1f control 3,432,607 3/1969 Bergman 84/ 1.17 keys in both whole tone scales are held, only the same 3,725,562 4/1973 Munch et al 84/ 1.24 keys and those in octave relation thereto in the minia- 3,198,055 8/1965 Von Gunten 84/l.17 X ture keyboard are live, 3,227,027 H1966 Von Gunten 84/l.l7 X 1 3,358,070 12/1967 Young 84/1.17 5 Claims, 2 Drawing Figures Loy 2R; Mfl/VUHL MIA/[#ZQUgE-F %2%" 28v 1 4 4 7 {2? lzzfligi/fl f 5 J c {/0 17 61 z C4505 5 C1 Kfg 'k 1a a b flil pa 2! ca ca 7 If j g 2 c4 {6' j f j j fia apps 6 MEAN/4L C5 c5 C5 zogg/ e ngggum OTHER B05555 c! film-,5 gg glr c 1: 11*: 0 0* a u 2 C1 C5, 10 KEYER KEYER L L i 44 c 4,.

5 7 a2 64 6a 6 m j 6/ 6? 6b 67 9 our/ 07 OUTPUT SYSTEM PATENTEDUEC'I 81975 SHEEI 2 0F 2 mu QQ mm mw QM ORGAN SYSTEM FOR AUTOMATICALLY PRODUCING RUNS OF VARIOUS CHARACTER BACKGROUND OF THE INVENTION 1. Field of the Invention Organ systems for automatically or semiautomatically producing complicated run effects customarily requiring a high order of playing skill.

2. Description of the Prior Art The most nearly similar prior art known to the applicant is exemplified by Young U. S. Pat. No. 3,358,070. In that arrangement a supplementary miniature keyboard capable of playing all of the notes in several octaves by stroking a finger along the keyboard is connected in series through special contacts in one of the main organ keyboards such that all of the contacts in the miniature keyboard are dead excepting those which correspond to the keys being held in the mainor control keyboard or notes in octave relation thereto. Thus, if in the main keyboard, the chord CEO is held, running a finger along the miniature keyboard from left to right plays the arpeggio CEGCEGCE etc. up the scale the number of notes in the series and the starting and finishing notes depending upon the starting and finishing points of the stroke. The reverse occurs if the miniature keyboard is stroked from right to left. In addition to the miniature keyboards shown in this Young patent, another device for the same purpose forms the subject of a US. Pat. application, Ser. No. 272,681 filed by Charles A. Dyle and John W. Edwards for Arpeggio Keyboard. This may be of interest, but reference thereto is not necessary since the particular form the supplemental miniature keyboard takes is incidental to the present invention.

SUMMARY OF THE INVENTION Although the previously mentioned Young patent discloses an arrangement for playing an arpeggio consisting of the notes held in one of the main keyboards, or notes in octave relation thereto, by the use of a miniature keyboard having contacts for all of the notes in the scale, the Young arrangement is limited to this mode of play. The present system includes this arpeggio mode of play of the Young patent, but automatically switches to one of two other modes of play when such other modes are more suitable. For example, if only one key is being held in the lower keyboard (the preferred keyboard for control purposes, although either could be used), the Young arpeggio arrangement will play only this one note and those octavely related thereto. This is considered an insufficient response to be of practical value. The system of the present invention under the same conditions (only one key held in the lower manual) makes available for play on the supplementary miniature keyboard the six notes of the whole tone scale of which the note held is a member.

For those who may not be familiar with the whole tone scales, it should be understood that there are two whole tone scales of six notes each which consist of notes a whole tone apart. The two are what will be referred to hereafter as the C whole tone scale consisting ofthe notes C, D, E, F# G A and the C whole tone scale consisting of notes C D F, G, A and B.

Thus, for instance, if the single note D is held in the lower manual, it will, of course, play in the usual manner from the lower manual resources, and if in addition the miniature keyboard is stroked from left to right, the upper manual keyers will play in succession C D E F# G A C D E F etc., depending upon how long the stroke is over the keys of the miniature keyboard and the points of beginning and ending.

Although the lower manual is used to control what keys are live in the miniature keyboard, it is suggested that the response to play on the miniature keyboard be from the resources of the upper keyboard where there usually is a better selection of tones suitable for solo play. Although either manual can be used for control and either setting or a special setting can be used to respond to the miniature keyboard, this description in the interest of definiteness will proceed upon the assumption that the lower manual keys will be used to determine the keys which are live (will play) on the miniature keyboard, but that the keyers actuated by the miniature keyboard will be those which normally respond to play upon the upper manual or separate keyers, preferably percussion keyers, using sources for the upper manual.

Play upon the upper manual, not shown since its structure and connections may be entirely conventional, has no effect upon operation of the system of this invention.

If more than one key is held in the lower manual, but all so held are within the same whole tone scale, play upon the supplementary keyboard will be the same as if a single key for any note in that whole tone scale was being held. Thus, the system gives a six note response under these conditions, but since there is no tonic, no identifiable key, the response cannot be out of keeping with the music being played.

If three or four keys are being held in the lower manual, this customarily will represent a recognized chord. A few of these have all notes within a single whole tone scale and in this case the live keys in the miniature keyboard will represent the six notes of that scale. Usually, however, the chord will have notes in both whole tone scales. Under theseconditions the live keys in the small keyboard will automatically be the three or four for the notes of the chord and those octavely related thereto. This is the musically preferred response and prevents the inadvertent play of accidentals and unsatisfactory intervals.

Under conditions where no keys are being held in the lower manual, the miniature keyboard of the Young patent has no live keys. With the present system under these conditions all miniature keys are live. When 1 stroked, therefore, the system plays the complete half tone scale, more properly designated the chromatic scale. This is the most suitable response under conditions where there is no lower manual note being held which suggests some other response as being more suitable.

Although these responses are completely automatic, they are nevertheless under the control of the musician. That is, if the musician desires one of the whole tone scales as a run, it is necessary merely to hold one key in the lower manual which is in that whole tone scale. If a complete chromatic scale is desired, all keys in the lower manual are momentarily released, and so on.

The important aspect of the invention from the musicians standpoint is that whenever the miniature keyboard is stroked, there is always some series of notes that play a run, and the series played is always suitable to the musical situation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a simplified circuit diagram showing a portion of the system and limited to avoid confusion to a singlefgrou'p of representative notes, the octave group of C notes, plus the busses for the other note groups; and

FIG. 2 is a diagrammatic representation of a circuit board which forms a portion of the system and is used in conjunction with the circuit of FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to FIG. 1 of the drawings, a 28 v. source is indicated at terminal 10. This source is connected by line 12 to one side of the contact sets operated by all of the keys of the lower manual. These contact sets are labeled l4, 16, 18, 20 and 22 for the playing keys for the notes C,, C C C and C respectively. The playing keys for actuating the contacts are indicated respectively by the numerals l5, l7, 19, 21 and 23. The lead from the other side of contact set 14 is connected to the cathode of diode 24, the anode of which is connected to a C bus 34. Similarly, the other contact sets 16, 18, 20 and 22 are connected through identically polariz ed diodes 26, 28, 30 and 32, respectively, to the C bus 34. The common point between contacts 14 and diode 24 is connected by a lead 36 to the lower manual keyer 38 for the C, note. When the contacts 14 are closed by pressing the lower manual C key 15, the 28 v. potential is applied to keyer 38 and this connects the lower manual C, tone signal source 40 to an output lead 42. The keyer 38 may be entirely conventional and operates in a conventional manner and needs no detailed description. The output lead 42 is connected to the output system 44 of the organ which may be conventional and, therefore, needs no description.

The output sidesof key contacts l6, 18, 20 aand 22 are similarly connected to the lower manual keyers for the notes C C,,, C, and C,-,, respectively. To avoid confusion, only one of these additional keyers, the one for C,,, is indicated at 46. Thus, whenever any lower manual C key is pressed, its keyer is turned on and the signal for the C note called for by that key is applied to the output 44. Simultaneously, playing any lower manual C key applies the 28 v. potential to the C bus 34 without distinction as between which C key is played. The diodes 24-32 provide isolation so that the 28 v. potential applied to the bus 34 by playing one C key cannot feed back and actuate the keyers for the other C notes.

The C bus 34 is connected by lead 48 to one side of a contact set 50 actuated by a key 51 for the C, note in the supplemental or miniature keyboard. This keyboard may be of the type previously discussed and needs no special description. Essentially, it may consist of several octaves of keys about one eighth inch wide without the usual distinction as between the black and white keys with each key having its own contact set.

Since these miniature keys are intended to be stroked in succession rather than for individual play, this keyboard can consist simply of the contact set in a row with a covering providing a smooth flexible surface for a finger to slide over as described in the previously mentioned patent and pending application.

The other side of the miniature key contact set is connected to a keyer 52 which when it receives a negative potential acts to connect the upper manual source 54 for the C, signal to the output 44. The keyer 52, which may be conventional, may be the same keyer used to connect the upper manual C, source to the output when the C, key in the upper manual is played, or it may be separate with a separate or the same C, source, depending upon the organization of the particular organ and the type of response desired. Preferably, the keyer 52 provides a percussive envelope.

The other C contact sets in the miniature keyboard, C C C C indicated respectively at 56, 58, 57a and 59a and actuated respectively by keys 53, 55, 57 and 59 are similarly connected between the C bus and their individual keyers for the appropriate C note. In the interest of avoiding confusion, only one of these additional keyers, for the C note, is shown and is indicated at 56.

Thus, playing any C key in the lower manual applies 28 v. potential to the C bus 34 and this makes all of the C keys in the miniature keyboard live, such that if any of them are pressed, the appropriate C note for that key is sounded by actuation of the proper keyers 52 or 56 or those in between.

This same arrangement is duplicated for each of the twelve note systems and since the circuits are alike, separate illustration and description of these is not necessary. For purpose of orientation, however, the busses for each of these, equivalent to the C bus 34, are shown and each of these busses is connected to its own terminal. These terminals are indicated by the numerals 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70 and 71 for the C, C# ,D,D# E,F,F# ,G,G# ,A,A andBbusses,

' respectively. In the interest of convenience of reference, those bus terminals in the C whole tone scale have even numbers and those in the C whole tone scale odd numbers. I

The system so far described is equivalent to the previ: ously mentioned Young system. Whatever keys are held in the lower manual will make live the same keys and those octavely related thereto in the miniature keyboard. The only substantial difference is that whereas the Young patented system provides an additional set of contacts under the playing keys of the lower manual for controlling the miniature keyboard, the present system uses the same lower manual key contacts both for regular play of the lower manual tone signal sources and for control of the miniature keyboard, isolation of the lower manual keyers from the busses, 34 for instance, being accomplished by the diodes 24-32 for example. So far as the player is concerned, no difference can be noted.

Referring to FIG. 2, a circuit board is shown with fourteen terminals along the lower edge. These are adapted for plug-in connection to a suitable holder. One of these terminals, 82, is for connection to ground and another, 84, receives a 28 v. supply. The remaining 12 terminals are connected to the twelve busses shown in FIG. 1 and for convenience, the terminals in FIG. 1 directly connected to the terminals in FIG. 2

have the same numbers in both figures. It will be noted that on the circuit board the six terminals toward the left are for notes forming the C whole tone scale whereas the six to the right constitute the C whole tonescale.

Each of the terminals to the left, 60, 62, 64, 66, 68, and 70 is connected to a common lead 86 by way of individual diodes 88, 90, 92, 94, 96 and 98, respectively. These diodes are polarized with their cathodes connected to the terminals. Also, each of the same terminals 60, 62,64, 66, 68 and .70 is connected through individual diodes 100, 102, 104, 106, 108 and 110, respectively, to a common lead 1 12. The diodes in this set are polarized with their anodes connected to the terminals.

The terminals to the right 61, 63, 65, 67, 69 and 71 are similarly connected through diodes 114, 116, 118, 120, 122 and 124 to a common lead 126. These diodes have their cathodes connected to the terminals. Similarly, also, the same terminals are connected to a common lead 140 by way of individual diodes 128, 130, 132, 134, 136 and 138, respectively. The diodes in this set have their anodes connected to the terminals.

Near the center of the figure two transistors are shown at 142 and 144. The emitters are connected together and to the 28 v. terminal 84 by way of a 1K resistor 146 and to ground terminal 82 by way of a 2.2K resistor 148. The common lead 86 is connected to the base of transistor 142 and to ground through a 22K resistor 149. Similarly, common lead 126 is connected to the base of transistor 144 and to ground through 22K resistor 150. The collector of transistor 142 is connected to common lead 140 and the collector of 144 is connected to common lead 112.

The system operates as follows. When no playing key is held in the lower manual none of the key contacts 14-22 or the equivalent for other notes will be closed and the 28 v. from terminal is not applied many of the busses 34 or the equivalent forother notes. Since the 28 v. potential is not applied to any of the terminals 60-71, the bases of the transistors 142 and 144 are both near ground at this point in the description. Under these conditions, the negative potential from terminal 84 and the voltage divider, resistors 146 and 148, applied to the emitters is sufficient to cause both transistors to conduct. The negative potential is, therefore, applied from the collectors through the diodes connected to the leads 112 and 140 to all of the terminals 0-71:

Although this negative potential at the terminals 60-71 is applied back to the transistor bases by way of the diodes connected to leads 86 and 126, the voltage drop through the two sets of diodes in series in each connection (about 0.6 v. per diode) is enough so that the bases of the transistors remain sufficiently positive relative to the emitters to insure that conduction through the transistors continues. Thus, when no key in the lower manual is held, all of the terminals 60-71 are at a potential which is not sufficiently negative to turn off the transistors 142 and 144, but it is more than enough negative to operate the keyers 52 and 56, and the equivalent for the other notes. Since the negative potential on the terminals 60-71 is connected to all of the busses, 34 or the equivalent for other notes, all of the keys in the miniature keyboard are live, and drawing a finger across the miniature keys can sound all of the notes for several octaves of the chromatic scale in succession, depending upon the number of miniature keys stroked.

If one key in the lower manual is held (or more than one if all are within the same whole tone scale), one of the C keys, for example, the 28 v. potential from terminal 10 is applied to the C bus 34, or the equivalent bus for other notes. If it is the C bus, this negative potential is applied to terminal 60. Since it is considerably more negative than the potential already there by way of conduction through transistor 144, this more negative potential is applied to the base of transistor 142 by way of conduction through diode 88. The base of transistor 142, therefore, becomes more negative than the emitter and the transistor ceases to conduct. This removes the negative potential from terminals 61, 63, 65, 67, 69 and 71. Since the negative potential is no longer applied to the busses (equivalent to the bus 34) for the notes C D F, G, A and B, the keys in the miniature keyboard for these notes go dead, but those for notes C, D, E, F G and A remain live. If now a finger is drawn across the miniature keys in succession, only the notes of the C whole tone scale will sound.

If a key for one of the notes in the C whole tone scale is held, or more than one if all are within the same whole tone scale, the same action takes place excepting that it is transistor 144 that is turned off. This renders dead all of the miniature keys which play notes in the C whole tone scale so that when a finger is drawn across the miniature keys, only the notes C D F, G, A and B play.

If a chord is held in the lower keyboard which has notes in both whole tone scales, CEG, for example, the busses for these notes receive the 28 v. potential from terminal 10 and this is applied to terminals 60, 64 and 67, or to other terminal combinations if other chords are played. This renders both transistors 142 and 144 nonconductive with the result that none of the busses connected to the terminals 60-71 have a negative potential thereon excepting those supplied directly from terminal 10 by way of the closed key contacts in the lower manual. Thus, if the chord CEG is held in the lower manual, only the miniature keys for the notes CEG will be live. Drawing a finger across the miniature keys, therefore, sounds only the notes CEGCEGCE- in succession.

Although the circuit of FIG. 2 is shown as organized upon a plug-in circuit board, this, of course, is not essential. An advantage, however, in addition to the usual advantages associated with circuit board use, which might not be apparent is that if desired, the organ can be supplied with the circuit of FIG. 1 to perform the automatic arpeggio functions identical to those of the Young patent previously mentioned. At a later date or as an alternative, the system can be converted to perform according to the present invention simply by plugging in the circuit board of FIG. 2. This is because all circuits on the board of FIG. 2 are simply connected as branches to those circuits existing in FIG. 1. It is not necessary, therefore, to interrupt or alter any of the circuits of FIG. 1 to make the change.

Note also, that the circuit of FIG. 2 uses the voltage divider, resistors 146 and 148, to apply a potential of about --19 v. to the emitters of transistors 142 and 144 from the board terminal 84 at 28 v. This specific arrangement is used simply as a matter of convenience so that the board can use a 28 v. potential source already available in the organ, at terminal for instance. If a source at about l9 v. were available in the organ it could, of course, be connected directly to the emitters, and resistors 146 and 148 could be omitted. Whatever the voltages supplied, the potentials remaining after conduction through the transistors 142 and 144 and diode connections should be sufficient to operate the keyers, 52 and 56 for instance, and the voltage at terminal 10 should be sufficient to turn off the transistors 142 and 144 when applied to the bases by way of the intervening diodes. If it is desired to have provision for deactivating the automatic feature, a switch may be placed in series with the ground connection 82, FIG. 2, removing forward bias from transistors 142 and 144 when the switch is opened.

I claim:

1. In an electronic organ system, a first manual and a second manual, connections enabling keys played in said first manual to sound musical notes appropriate to the keys played and for supplying a potential to the same note keys and those in octave relation thereto in said second manual, and connections for the playing keys in the second manual to sound notes for the second manual keys played which receive a keying potential, a second and a third keying potential supply for said second manual, said second supply being connected to keys in said second manual for notes in the C whole tone scale, said third supply being connected to keys in said second manual for notes in the C whole tone scale, and means for interrupting the second or third potential supply connections when keys in the first said manual are played in the C or C whole tone scales respectively and for interrupting both the second and third potential supply connections if keys are played simultaneously in the first said manual for notes in both the C and the C whole tone scales.

2. An electronic organ system as called for in claim 1 in which said second and said third keying potential supplies are at a less potential than the first said keying potential, and in which the keying potential from any of the first, second or third potential supplies is sufficient to sound notes according to keys played in said second manual.

3. In an electronic organ system in which keys in one manual supply keying potentials from a source in response to the keys played: keyers connected to sound notes in response to said keying potentials, twelve terminals, each of said terminals being connected to a single key and all other keys octavely related thereto to receive said potential when one of the keys in its octave group is played in said manual, said terminals representing notes in the C whole tone scale and notes in the C whole tone scale, a second manual, a normally on source of keying potential for the second manual keys for the C whole tone scale, a normally on source of keying potential for the second manual keys for the C whole tone scale, means for turning off the normally on source for the second manual keys in the C whole tone scale responsive to a potential from the first said source at a terminal representative of any note in the C whole tone scale, means for turning off the normally on source for the second manual keys in the C whole tone scale responsive to a potential from the first said source at a terminal representative of any note in the C whole tone scale, means connecting said terminals to keys of like name in said second manual, and keyers connected to said second manual and adapted to sound notes in response to keys played in said second manual if the keys played in said second manual have a keying potential applied thereto from either the first said source or one of said normally on sources.

4. In an electrical musical instrument, a source of several octaves of electrical tone signals for the chromatic musical scale, an output, system, keyers connected for supplying said tone signals individually to said output system in response to the supply of a potential of at least a certain value to said keyers individually, a manual of playing keys connected for supplying said potential to said keyers individually according to keys played when said potential is supplied individually to keys in said manual, a first source for supplying said potential, circuit means connecting said first source to the keys in said manual for notes in the C whole tone scale, a second source for supplying said potential, circuit means connecting said second source to the keys in said manual for notes in the C whole tone scale, each of the last saidcircuit means having means for interrupting its connection in response to the application thereto of a keying potential having a value a predetermined amount in excess of the first said keying potential but not in response to a potential at the level of the first said potential, a third source of keying potential, said third source having said potential value at a predetermined amount in excess of the first said keying potential, a second manual of playing keys, means including keys in said second manual for connecting said third source to playing keys in the first said manual in unison and those in octave relation to keys played in said second manual, circuit means connected for supplying substantially the potential supplied by each of the playing keys of the first said manual in the C whole tone scale to the interrupting means for the connecting means for said second source and for supplying substantially the potential supplied by each of the playing keys of the first said manual in the C whole tone scale to the interrupting means for the connecting means for said first source.

5. In an electrical musical instrument as called for in claim 4, an additional set of keyers connected for supplying tone signals individually to the output system in response to a keying potential supplied individually to said additional set of keyers, and circuit means including said third source of potential and said second manual connected for supplying the last said potential individually to said additional set of keyers in response to keys played in said second manual.

* It 1* k I. 

1. In an electronic organ system, a first manual and a second manual, connections enabling keys played in said first manual to sound musical notes appropriate to the keys played and for supplying a potential to the same note keys and those in octave relation thereto in said second manual, and connections for the playing keys in the second manual to sound notes for the second manual keys played which receive a keying potential, a second and a third keying potential supply for said second manual, said second supply being connected to keys in said second manual for notes in the C whole tone scale, said third supply bEing connected to keys in said second manual for notes in the C whole tone scale, and means for interrupting the second or third potential supply connections when keys in the first said manual are played in the C or C whole tone scales respectively and for interrupting both the second and third potential supply connections if keys are played simultaneously in the first said manual for notes in both the C and the C whole tone scales.
 2. An electronic organ system as called for in claim 1 in which said second and said third keying potential supplies are at a less potential than the first said keying potential, and in which the keying potential from any of the first, second or third potential supplies is sufficient to sound notes according to keys played in said second manual.
 3. In an electronic organ system in which keys in one manual supply keying potentials from a source in response to the keys played: keyers connected to sound notes in response to said keying potentials, twelve terminals, each of said terminals being connected to a single key and all other keys octavely related thereto to receive said potential when one of the keys in its octave group is played in said manual, said terminals representing notes in the C whole tone scale and notes in the C whole tone scale, a second manual, a normally on source of keying potential for the second manual keys for the C whole tone scale, a normally on source of keying potential for the second manual keys for the C whole tone scale, means for turning off the normally on source for the second manual keys in the C whole tone scale responsive to a potential from the first said source at a terminal representative of any note in the C whole tone scale, means for turning off the normally on source for the second manual keys in the C whole tone scale responsive to a potential from the first said source at a terminal representative of any note in the C whole tone scale, means connecting said terminals to keys of like name in said second manual, and keyers connected to said second manual and adapted to sound notes in response to keys played in said second manual if the keys played in said second manual have a keying potential applied thereto from either the first said source or one of said normally on sources.
 4. In an electrical musical instrument, a source of several octaves of electrical tone signals for the chromatic musical scale, an output system, keyers connected for supplying said tone signals individually to said output system in response to the supply of a potential of at least a certain value to said keyers individually, a manual of playing keys connected for supplying said potential to said keyers individually according to keys played when said potential is supplied individually to keys in said manual, a first source for supplying said potential, circuit means connecting said first source to the keys in said manual for notes in the C whole tone scale, a second source for supplying said potential, circuit means connecting said second source to the keys in said manual for notes in the C whole tone scale, each of the last said circuit means having means for interrupting its connection in response to the application thereto of a keying potential having a value a predetermined amount in excess of the first said keying potential but not in response to a potential at the level of the first said potential, a third source of keying potential, said third source having said potential value at a predetermined amount in excess of the first said keying potential, a second manual of playing keys, means including keys in said second manual for connecting said third source to playing keys in the first said manual in unison and those in octave relation to keys played in said second manual, circuit means connected for supplying substantially the potential supplied by each of the playing keys of the first said manual in the C whole tone scale to the interrupTing means for the connecting means for said second source and for supplying substantially the potential supplied by each of the playing keys of the first said manual in the C whole tone scale to the interrupting means for the connecting means for said first source.
 5. In an electrical musical instrument as called for in claim 4, an additional set of keyers connected for supplying tone signals individually to the output system in response to a keying potential supplied individually to said additional set of keyers, and circuit means including said third source of potential and said second manual connected for supplying the last said potential individually to said additional set of keyers in response to keys played in said second manual. 